The present invention relates internal combustion engines and more particularly to an improved sealing arrangement for a replaceable wet cylinder liner.
Over the decades internal combustion engines have evolved with basically two different types of block configurations. The integral bore cylinder block and replaceable cylinder liner types of which there are two configurations top flanged liner with spacer plate and block combination and the mid supported liner spacer deck block arrangement.
The incorporation of the replaceable liners in the design of an engine provides numerous advantages to the manufacturer and the end user in addition to the obvious benefit of allowing such liners to be replaced during overhaul of the engine. These liners are usually wet liners and are provided with a sealing arrangement at the top and bottom of the outside diameter of the liner. The sealing arrangement at the top and bottom create an open volume or passage defined around the liner exterior and the block for flow of coolant.
Such sealing arrangements for the top part of the wet cylinder liners adjacent to the head have long been part of the art. In this arrangement, the top guiding portion of the liner follows directly below a sealing arrangement in order to provide good guidance and to provide good contact with the block. One such arrangement is disclosed in U.S. Pat. No. 4,417,549 and issued on Nov. 29, 1983 to Ulrich Kazenmaier and assigned to M.A.N. Maschinenfabrik. Maschinenfabrik. This design uses two spaced apart o-rings directly below the flange seat to perform the sealing. Since o-rings are used two grooves or recesses, cut into the exterior of the cylinder liner above the guide portion, are required at a depth sufficient to retain the position of the o-rings from axial movement and hold them to a diameter to provide the sealing. This creates two separate points for fatigue at the top portion of the liner in a highly stressed area under the flange seat.
The present invention is directed to overcome one or more of the problems as set forth above.
In one aspect of the present invention a sealing arrangement is provided for a replaceable cylinder liner of an internal combustion engine. The sealing arrangement includes an annular groove positioned in an outer surface of the cylinder liner adjacent a flange seat and extending in an axial direction towards a guide portion. The annular groove has a first undercut positioned at the intersection of the flange seat and a vertical wall portion of the annular groove and a second undercut positioned at the intersection of the vertical wall portion and a horizontal leg portion of the annular groove.